Washington: Using sharp language against Pakistan, US President Barack Obama on Sunday said that the Nawaz government can and must take more effective action against terrorist groups that operate from its territory.

Obama also said that the increasing insecurity inside Pakistan is a threat to its own stability.

Further describing the terror attack on Punjab's Pathankot Iandian Air Force base as an "another example of the inexcusable terrorism that India has endured for too long", Obama gave credit to Prime Minister Narendra Modi for reaching out to his Pakistani counterpart Nawaz Sharif after the attack.

“Both leaders are advancing a dialogue on how to confront violent extremism and terrorism across the region,” Obama told reporters in an interview to PTI in Washington during which he answered a wide range of questions covering Indo-US ties, terrorism and outcome of the Paris climate change summit.

Voicing his belief that the Indo-US relationship can be one of the defining partnerships of the century, Obama said that Modi shared his enthusiasm for a strong partnership and “we have developed a friendship and close working relationship, including our conversations on the new secure lines between our offices”.

Asked if the relationship has achieved its full potential, the President replied, “Absolutely not.”

On the Pathankot attack, Obama said, “We join India in condemning the attack, saluting the Indians who fought to prevent more loss of life and extending our condolences to the victims and their families. Tragedies like this also underscore why the US and India continue to be such close partners in fighting terrorism.”

Obama was of the view that Sharif recognised that insecurity in Pakistan is a threat to its own stability and that of the region. After the December, 2014 school massacre in Peshawar he had vowed to target all militants, regardless of their agenda or affiliation.

“That is the right policy. Since then, we have seen Pakistan take action against several specific groups. We have also seen continued terrorism inside Pakistan such as the recent attack on the university in north west Pakistan,” he added.

“Pakistan has an opportunity to show that it is serious about delegitimising, disrupting and dismantling terrorist networks. In the region and around the world, there must be zero tolerance for safe havens and terrorists must be brought to justice,” the US Prez asserted in this third interview to reporters.